1. Field of the Invention
This invention relates to the field of computer processing and, more particularly, to data storage libraries.
2. Description of the Related Art
Modern businesses increasingly own large numbers of computers, servers, and other information technology (IT) infrastructure, all of which may produce and process increasingly large amounts of data. In some instances the vast majority of this data may be discarded, but in other instances significant amounts of data must be stored and maintained in a storage library.
Storage libraries may be operable to store and retrieve storage media for reading and writing by an external computer system. Storage media may be tapes, discs, or other media which are typically operable to store tens of gigabytes or more per unit. Each storage media unit is typically stored within a slot, or storage area, and transported to and from a compatible media drive or access portal by a “picker”. Sizes of storage media libraries may differ greatly, with some configurations holding only a handful of media units and a single drive, while others hold hundreds or thousands of media units and dozens of drives.
One or more external computers may be attached to the storage library by means of a network or data connection. These computers may be operable to access the media drives and to issue commands to move storage media units to and from various slots and drives via the picker, thereby giving any computer connected to the storage library the ability to access any media unit within the library at any time without human intervention.
A computer connected to the storage library may typically address storage targets such as slots, media units, drives, portals, and pickers within the library by a logical identifier. However, such logical identifiers typically give no indication as to the storage targets' relative spatial locality. For example, a computer may be unable to distinguish between a slot located close to a specific drive and a slot located far from the drive. Accordingly, an external computer is typically unable to lay out media in an efficient manner, which may in turn cause delays in retrieving and storing media units within the storage library.